I've just posted the following in another thread whose subject is supernatural experience, but it may deserve its own thread so I'll repost it here. I don't believe in the supernatural but I do believe that people experience unexplained things. Where I differ from some people is that I perceive the unexplained things exist only in their brains and not in the physical world around them.
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Perhaps one needs only to contemplate the meaning of reality. Reality exists only in one place, and that is your brain. Your eardrums vibrate at frequencies between 20 and 20,000 Hz and send signals through your auditory complex into your brain, and your brain interprets them as sound. The rods and cones in your eyes are similarly limited to specific wavelengths of light and colour that are sent as signals to your visual cortex in your brain which interprets them. Same goes for your sense of smell, taste and feel. They are signals picked up by your body and interpreted by your brain.
Almost 20 years ago I was commuting to various places in Canada and the United States troubleshooting production facilities. For two years I spent 36-48 hours at home and the rest of the time in airports, airplanes, hotel and motel rooms, factories, automobiles and offices. There were times I would wake up in the morning and have to concentrate to remember where I was.
I was in Atlanta, Georgia, can't remember the name of the hotel, when the alarm beside my bed went off at 5:00 in the morning. I was to attend a meeting in Augusta at 9:00 and had to make my way to the airport for an early flight. The room was pitch black but for the red blinking light in the smoke detector mounted on the ceiling. I reached over to the bedside light and turned it on, then silenced the alarm. I got out of bed, walked to the bathroom, turned on the light, urinated, shaved and showered. All this took about 7-8 minutes. I was towelling myself off as I walked out of the bathroom and I looked over at the bed to see myself asleep in it. I stopped in my tracks and stared for only a few seconds when the alarm went off and I opened my eyes to a pitch black room with only a little red blinking light on the ceiling.
This experience was what is called a lucid dream. I could see every detail in the room, my slightly bloodshot eyes and the unkempt state of my hair in the mirror. I could smell my urine, the soap and the shampoo, feel the bristle of my morning beard giving way to the razor and the hot water flowing over my skin, hear the rush of the shower and my thoughts as I put together the sequence of the day ahead of me. It was all very real but it was not real. I was fully conscious but I was also asleep. It was only a dream generated by my brain but because everything was entirely plausible, normal, I did not recognise that I was dreaming.
I related the experience to a co-worker who told me that he had devoted considerable time to learning about the phenomenon, including training himself to dream lucidly. A week or so later he gave me a book on the subject - there are many, this one was Jungian - which went into history, culture and practice (including, for example, the Senoi tribe in Malaysia).
I have had other lucid dreams but in every case I have been able to recognise that I was dreaming because of implausible details generated by my brain. An oversized rocking horse, a strange being or place never before seen, talking with friends and family who are no longer alive, flying like a bird over tropical forests that look like giant broccoli down below. I have been able to prolong a lucid dream, recognising completely that it is a dream but enjoying the experience to the fullest. I have also been able to terminate it instantly when the experience being manufactured by my brain was unpleasant. In all cases I awoke in my bed remembering every detail but recognising that it was not real.
Your brain is capable of some incredible things but those things exist only in your head.